Method for controlling the movement of a boom, and work machine

Abstract

A method controls the movement of a boom, wherein the boom is moved by a plurality of hydraulic drives. Each hydraulic drive is fed with a hydraulic medium, the pressure and/or volume flow of which is adjustable. The method predefines a desired direction of movement and a desired speed of a boom tip; predictively calculates a pressure and/or a volume flow required for each of the hydraulic drives that are required for the desired direction of movement and desired speed; subsequently generates a supply pressure depending on the predictively calculated pressures and/or subsequently generating a supply volume flow as a function of the predictively calculated volume flows; and subsequently feeds the hydraulic drives required for the desired direction of movement and desired speed with the hydraulic medium having a respective feed pressure and/or a respective feed volume flow such that the boom tip moves in the desired direction of movement at the desired speed.

What is claimed is: 
     
       1. A method for controlling movement of a boom, the boom being moved by way of a plurality of hydraulic drives, a respective hydraulic drive being fed with a hydraulic medium, a pressure of which and/or a volumetric flow of which is settable, the method comprising the steps of:
 specifying a desired movement direction and a desired speed of a boom tip; 
 predictively calculating a respective required pressure and/or a respective required volumetric flow for one or more hydraulic drives which are required for the desired movement direction and the desired speed based on measured values of sensors which detect an instantaneous load of the boom and based on a boom model; 
 subsequently generating a supply pressure in a manner which is dependent on the predictively calculated pressures and/or subsequently generating a supply volumetric flow in a manner which is dependent on the predictively calculated volumetric flows; and 
 subsequently feeding the one or more hydraulic drives which are required for the desired movement direction and the desired speed with the hydraulic medium at a respective feed pressure and/or a respective feed volumetric flow such that the boom tip moves in the desired movement direction at the desired speed. 
 
     
     
       2. The method as claimed in  claim 1 , wherein
 a supply line is loaded with the supply pressure and/or the supply volumetric flow is conducted in the supply line, and 
 a respective feed pressure is derived from the supply pressure and/or a respective feed volumetric flow is derived from the supply volumetric flow. 
 
     
     
       3. The method as claimed in  claim 1 , wherein
 the generating of the supply pressure comprises the steps of:
 determining a highest load pressure under the respective predictively calculated pressures, and generating the supply pressure in a manner which is dependent on the determined highest load pressure. 
 
 
     
     
       4. The method as claimed in  claim 1 , wherein
 at least part of the hydraulic drives are hydraulic cylinders. 
 
     
     
       5. The method as claimed in  claim 1 , wherein
 the supply pressure and/or the supply volumetric flow are generated by a single hydraulic pump. 
 
     
     
       6. A work machine, comprising:
 a boom; 
 a plurality of hydraulic drives which are configured to move the boom, a respective hydraulic drive being fed with a hydraulic medium, the pressure of which and/or the volumetric flow of which is settable; 
 a setting device, by which a desired movement direction and a desired speed of a boom tip is specified, 
 a computing unit which is configured to predictively calculate a respective required pressure and/or a respective required volumetric flow for one or more hydraulic drives which are required for the desired movement direction and the desired speed based on measured values of sensors which detect an instantaneous load of the boom and based on a boom model; 
 a pressure generating device and/or a volumetric flow generating device configured, following the predictive calculating, to generate a supply pressure in a manner dependent on the predictively calculated pressures and/or a supply volumetric flow in a manner dependent on the predictively calculated volumetric flows; and 
 a feed device configured to bring about subsequent feeding of the one or more hydraulic drives which are required for the desired movement direction and the desired speed with the hydraulic medium at a respective feed pressure and/or a respective feed volumetric flow such that the boom tip moves in the desired movement direction at the desired speed. 
 
     
     
       7. The work machine as claimed in  claim 6 , wherein
 the work machine is a mobile crane or an aerial work platform. 
 
     
     
       8. The work machine as claimed in  claim 6 , wherein
 the work machine is an auto concrete pump.